Pure and Helpful

Deuteronomy 22-23:  http://www.biblegateway.com/passage/?search=deu%2022-23&version=NIV
           Deuteronomy 22 begins with the oddest collection of laws:  regulations about helping a neighbor with his livestock, regulation about cross-dressing, about eating birds, about mixing seeds, etc.  Let me suggest at least two underlying principles.
            First, there is a concern here for what Christians name sins of omission.  Christian theology actually has a whole vocabulary for sin, and we contemporary Christians might do well to recover it and use it more often.  So, the basic distinction is between original sin and actual sin.  Original sin is the corruption of our nature that we have inherited from Adam; it is the cause and source of actual sins. Actual sins are all those thoughts, words, and deeds which run contrary to the will of God.  Further, actual sin has two 'expressions:' sins of commission, in which we actively violate something the Lord has said, and sins of omission, in which we fail to do the good at hand.  Deuteronomy 22 and its command to take care of lost animals is a reminder, "Don't fail to help your neighbor."
            Second, there is a concern here for purity.  I doubt there's any great, deep significance to 'cross-dressing,' mixed crops, or mixed weave clothes.  But there is an underlying principle:  let things be what they are, and don't try to make one thing into another.  Why?  Well, because God made it what it is, for one thing.    And because it reminds you that you are one thing--God's holy people--and you shouldn't act like something else.